The product recovery unit operations and their combination is not a recent innovation, but has accompanied the history of product recovery since the nineteenth century. Although educt–product or product–side product separation would not need to be performed, real bioprocesses may not go to complete conversion and may also utilize educt mixtures. Therefore, product recovery and purification remain key determinants of the viability of a whole bioprocess. This article provides an introduction to product recovery and some of its historical backgrounds. The integral view on product recovery is based on the modular operations of recovery of solids and liquids, cell treatment, solvent extraction, liquid–liquid phase separation, crystallization and precipitation, adsorption, distillation, chromatography, and membrane filtration. The scalability, yield per step, and number of unit operations in downstream processing are key factors to the economics of product recovery.
